Skip to content

dig.md

Latest commit

 

History

History
169 lines (130 loc) · 6.58 KB

dig.md

File metadata and controls

169 lines (130 loc) · 6.58 KB

Understanding dig Command Output

The default output of dig contains several sections including the header, question section, answer section, authority section, and additional information. Let's break down each section and learn how to filter specific parts using options.

$ dig tetsuya.dev

; <<>> DiG 9.10.6 <<>> tetsuya.dev
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 759
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;tetsuya.dev.			IN	A

;; ANSWER SECTION:
tetsuya.dev.		300	IN	A	172.67.217.28
tetsuya.dev.		300	IN	A	104.21.24.54

;; Query time: 79 msec
;; SERVER: 2407:c800:7f01:2000:219:110:2:24#53(2407:c800:7f01:2000:219:110:2:24)
;; WHEN: Wed Jun 15 06:36:41 UTC 2022
;; MSG SIZE  rcvd: 72

+cmd

Shows the version of dig being used and the global options. This is useful for documentation and troubleshooting purposes as it explicitly shows which version and options are active.

$ dig +noall +cmd tetsuya.dev

; <<>> DiG 9.10.6 <<>> +noall +cmd tetsuya.dev
;; global options: +cmd

+ques[tion]

Displays only the question section of the dig output. This shows what exactly was queried, including the domain name, record class (typically IN for Internet), and record type (defaulting to A record if not specified).

$ dig +noall +ques tetsuya.dev
;tetsuya.dev.                   IN      A

+ans[wer]

Shows only the answer section from the DNS response. This contains the actual DNS records returned by the server, including the TTL (Time To Live), record class, type, and value.

$ dig +noall +answer tetsuya.dev
tetsuya.dev.		300	IN	A	172.67.217.28
tetsuya.dev.		300	IN	A	104.21.24.54

+short

A simplified output format that only shows the essential answer data. This is particularly useful when scripting or when you only need the raw DNS values without any additional metadata.

$ dig +short tetsuya.dev
104.21.24.54
172.67.217.28

+sta[ts]

Displays timing and server statistics from the query. This includes query response time, which DNS server was used, when the query was made, and the size of the response message.

$ dig +noall +stats tetsuya.dev
;; Query time: 43 msec
;; SERVER: 2407:c800:7f01:2000:219:110:2:24#53(2407:c800:7f01:2000:219:110:2:24)
;; WHEN: Wed Jun 15 06:37:24 UTC 2022
;; MSG SIZE  rcvd: 72

Use different DNS server (@server)

The @server parameter allows you to query specific DNS servers directly. This is useful for testing different DNS providers or troubleshooting DNS propagation issues.

Cloudflare Public DNS

$ dig @1.1.1.1 +noall +answer +stats tetsuya.dev
tetsuya.dev.		300	IN	A	104.21.24.54
tetsuya.dev.		300	IN	A	172.67.217.28
;; Query time: 329 msec
;; SERVER: 1.1.1.1#53(1.1.1.1)
;; WHEN: Wed Jun 15 06:40:20 UTC 2022
;; MSG SIZE  rcvd: 72

Google Public DNS

$ dig @8.8.8.8 +noall +answer +stats tetsuya.dev
tetsuya.dev.		300	IN	A	172.67.217.28
tetsuya.dev.		300	IN	A	104.21.24.54
;; Query time: 92 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Jun 15 06:40:30 UTC 2022
;; MSG SIZE  rcvd: 72

Query type {A|MX|TXT|CNAME|NS}

You can query different types of DNS records by specifying the record type. Common types include:

  • A: IPv4 address records
  • MX: Mail exchange records
  • TXT: Text records (often used for verification)
  • CNAME: Canonical name records (aliases)
  • NS: Nameserver records
$ dig +short NS tetsuya.dev
thomas.ns.cloudflare.com.
jocelyn.ns.cloudflare.com.

+trace

Performs an iterative query that shows the complete DNS resolution process, starting from the root servers down to the authoritative nameserver for the domain. This is invaluable for understanding and troubleshooting the DNS resolution chain.

$ dig +trace tetsuya.dev

; <<>> DiG 9.10.6 <<>> +trace tetsuya.dev
;; global options: +cmd
.			511067	IN	NS	a.root-servers.net.
.			511067	IN	NS	b.root-servers.net.
.			511067	IN	NS	c.root-servers.net.
.			511067	IN	NS	d.root-servers.net.
.			511067	IN	NS	e.root-servers.net.
.			511067	IN	NS	f.root-servers.net.
.			511067	IN	NS	g.root-servers.net.
.			511067	IN	NS	h.root-servers.net.
.			511067	IN	NS	i.root-servers.net.
.			511067	IN	NS	j.root-servers.net.
.			511067	IN	NS	k.root-servers.net.
.			511067	IN	NS	l.root-servers.net.
.			511067	IN	NS	m.root-servers.net.
.			511067	IN	RRSIG	NS 8 0 518400 20200629050000 20200616040000 48903 . aWTFYLbKkhzdBbDxrCPRpJSnEsvwvspYZgJW5NlUmY321DG+yPa6i1z3 YXuNJaBJx0r/XHREn8L9yDJBJWVjmS6VYl7pQLzAXU9B4p889J1PoZoV 8dhG0HNMxda1jfotGCG+xRiLczPLGxMC4fi4wrxYQUj0G2c+dggThwsy T1eRqr74CcU+Ube/RZ09q3li3zg/UxzIVpmbCMmi1gtz93XuhHhcbs3l lVeCo90eaCk7n9Ay9cHOQRKlf7pRwiKLGDznKtI3m+PLpALeMgJzYjsz MKHlvlChy0ss1Utd24u6c9ikeA5dfg6C65f/5eMpqUCF+/KbaEIUoFp/ yzpNew==
;; Received 525 bytes from 1.1.1.1#53(1.1.1.1) in 24 ms

dev.			172800	IN	NS	ns-tld1.charlestonroadregistry.com.
dev.			172800	IN	NS	ns-tld2.charlestonroadregistry.com.
dev.			172800	IN	NS	ns-tld3.charlestonroadregistry.com.
dev.			172800	IN	NS	ns-tld4.charlestonroadregistry.com.
dev.			172800	IN	NS	ns-tld5.charlestonroadregistry.com.
dev.			86400	IN	DS	60074 8 2 B942E2CE5AEBF62FCA59D05707E6DBB795211D540D8ADBA02E9E89E8 33424785
dev.			86400	IN	RRSIG	DS 8 1 86400 20200629050000 20200616040000 48903 . kM+Q1cGw0xXAJErILQn9b+xsSrl7cLQk47yU85GNf7+uEvlI4BLRG+L4 1o0cx7FFrveK23dtcMw2Jc+Kha1QPSbw1E6X09XniMDXoezqhF31s0fr yKK3Y2kkxXQpHUVT/NxXWLbJ6ZAi3ctWI6Woh2SbBzb86Ggmma5EDbnG v6rDvOZaEfg/RDO4ccXpSxv9kJNY8mZNlB3hk+gLqlLM2GnWfLC+pnN/ nUJJP15zk8qV+hokk8NXUIC2mmO7QFjbK0+6bIXS2Yq1pvfZYkLumKgb LoWiuaVWcAK3S/rKEKuNW6JGX38DSw2CcROayyvV86zuMhIhKDo7kVj5 zdiaaA==
;; Received 731 bytes from 199.7.83.42#53(l.root-servers.net) in 134 ms

tetsuya.dev.		10800	IN	NS	ns-cloud-a1.googledomains.com.
tetsuya.dev.		10800	IN	NS	ns-cloud-a2.googledomains.com.
tetsuya.dev.		10800	IN	NS	ns-cloud-a3.googledomains.com.
tetsuya.dev.		10800	IN	NS	ns-cloud-a4.googledomains.com.
0rgudcvqtbf3oand8leokj1f7pk73qiu.dev. 300 IN NSEC3 1 0 1 B7B0891083980E59 0RH185F5P63J2D8I8NKQM07F33LJ80CU  NS
0rgudcvqtbf3oand8leokj1f7pk73qiu.dev. 300 IN RRSIG NSEC3 8 2 300 20200704202942 20200612202942 56224 dev. Yxuto/A4xoN8hpN9QlG4TXOAuPJ5+7j4qUT2bV20TfeREGVh1JfkaniU VhMHull4VTW0H6ORR7TKRW+DBXSx/g0nha9JTPYhQHk81R15b4AXm/qm lmbtUofnEFOtY2ndKxtFrPBbEevw+BYH6FC8k1R9PQEEdQE6JU1Ccv/r XRw=
;; Received 406 bytes from 216.239.32.105#53(ns-tld1.charlestonroadregistry.com) in 42 ms

tetsuya.dev.		3600	IN	A	104.198.14.52
;; Received 56 bytes from 216.239.38.106#53(ns-cloud-a4.googledomains.com) in 81 ms